The present disclosure relates to subject matter contained in Japanese Patent Application No. 10-164651 (filed on Jun. 12, 1998), which is expressly incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to a foreign body-recovering instrument for an endoscope that is removably inserted into an instrument-inserting channel of an endoscope to recover a foreign body from a body cavity, for example, a swallowed dental crown.
2. Description of the Prior Art
In general, a foreign body-recovering instrument for an endoscope has a plurality of foreign body-catching arms provided at the distal end of a flexible sheath that is removably inserted into an instrument-inserting channel of an endoscope. The foreign body-catching arms are opened or closed by remote control conducted at the proximal end of the sheath. Each foreign body-catching arm has a claw-like portion projecting from the inner side thereof. The claw-like portion is pressed against a foreign body when the foreign body-catching arms are closed to hold the foreign body.
In actual use of such a conventional foreign body-recovering instrument, a foreign body is caught by pinching it with the foreign body-catching arms from outside the foreign body.
As shown in FIGS. 22 to 24 by way of example, the foreign body to be recovered may be an object having a smooth surface such as a dental crown 101, or a thin metal piece such as a coin 102, or a tubular small article 103. In such a case, the foreign body is slippery and hence difficult to pinch with the foreign body-catching arms 50. Therefore, there are not a few cases where it is difficult to recover the foreign body.
In particular, when a foreign body 100 is lodged in a narrow tubular cavity such as a bronchial tube as shown in FIG. 25, it is difficult to open the foreign body-catching arms 50 in excess of the outer diameter of the foreign body 100 and hence impossible to pinch it. Accordingly, it is extremely difficult to recover the foreign body 100.